


IJACF Smut

by white_crayon



Category: Undertale
Genre: Ecto-Genitalia (Undertale), Ecto-Penis (Undertale), Ecto-Tongue (Undertale), Ecto-Vagina (Undertale), Ectobiology, M/M, Masturbation, beware the woman who is bad at tagging
Language: English
Status: Completed
Published: 2017-09-21
Updated: 2017-09-21
Packaged: 2019-01-01 03:51:56
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 1,229
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/12148029
Author URL: https://archiveofourown.org/users/white_crayon/pseuds/white_crayon
Summary: This is a chapter that was added to I'm Just a Circus Freak. I'm changing the formatting again, so the chapter no longer fit, but I still wanted to share it with the Archive, so I'm putting it here as a oneshot. You shouldn't need to read IJACF to understand it, but it might be a good idea (shameless plug). Anyways, enjoy this pure sin!





	IJACF Smut

Sans was used to waking up in a cold sweat from nightmares, but it was very rare that he woke up wet from anything else.  
So when his eyes shot open to find that the sheets were sticky, clinging to their legs, blue and orange shining through, he was a little shocked. Even more so when he realized that it was’t from him.  
Papyrus’ face was tinted orange, glowing softly in the darkness of the caravan. Soft noises were escaping him, little whimpers and moans that had Sans shivering. He lifted the blankets a little and peeked underneath to see an erection of mostly orange magic, cum dripping down the shaft and pooling at the head. The arousal from whatever dream Paps was having resonated in his soul and he moaned softly, draping an arm across his face. Part of him wanted to wake Papyrus, but he didn't want to risk his brother getting embarrassed and shutting this down. Their dick twitched, a bead of pre forming at the tip in his arousal. It had been so fucking long, and the universe had quite literally dropped this opportunity in his lap. Pushing the guilt out of his head for the time being, Sans shifted and wrapped his hand around the magic, giving it a few quick pulls.  
The effect on the still-sleeping Papyrus was well worth it. “Hngh...” he moaned, eyes scrunching up. He looked so beautiful like this, and Sans gave a soft sigh as he established a steady rhythm.  
As usual on the rare occasions they were able to do something like this, Sans’ thoughts turned to Papyrus. More specifically, a separate Papyrus with his own body. He sometimes felt a little guilty about thinking that way, but it wasn’t like he wished they were separated. Maybe sometimes he did, but mostly always because he wanted to see Paps. Feel every inch of his bones, gaze down at him in his whole self, or maybe up at him as they came together in a totally different way.  
He gave a pleasantly surprised moan as the thought caused their magic to react further, an entrance forming at the base of their pelvis. Contrary to the leaking cock, the cunt was primarily blue magic, but was just as wet and immediately sent a shock of arousal up Sans’ spine. Papyrus seemed to like it too, whimpering into his pillow as his spine curled forward. Sans paused in his movements for a moment to make sure he wouldn’t wake up before resuming.  
Back in his fantasies, Papyrus was bobbing his head over his dick, tongue working dirty magic while he looked up at his big brother through hooded eyes.  
“Fuck!” Sans hissed, the image sending shocks of pleasure through him.  
In his head, Papyrus didn’t stop, didn’t reprimand him for his language, just curled his tongue around Sans’ dick and bobbed his head. Sans groaned and brought a hand to his ribcage, teasing his phalanges over the bones.  
And suddenly that hand was joined by another, and Sans’ eyes shot open. Papyrus was twisted slightly so he was facing Sans, eye sockets heavily lidded and a wisp of orange magic escaping from his left socket.  
“You’re having fun without me,” he whispered, voice husky with arousal and sleep. The sound of it caused Sans’ spine to turn to jelly, and he flushed bright blue in the darkness of the room.  
“I th-thought--“  
Papyrus shushed him, fingers deftly pressing into each and every one of Sans’ sensitive spots. “I was having the most wonderful dream,” he murmured, the orange glow of a tongue showing behind his teeth. “Would you like to hear about it, brother?”  
Sans gulped, swallowing the lump in his metaphorical throat. “S-S-Sure.”  
Papyrus’ hand trailed down, and Sans’ breath escaped him as it brushed over the bulge in the sheets. The pleasure was mutual, as Papyrus’ eyes fluttered at the contact.  
“We were in the ring,” he started, peeling the soaked sheets off of their thighs, revealing their pelvis and mix matched magic. Sans hand was still wrapped around their cock, stroking absently. Papyrus’ hand joined in and they both moaned. Sans’ other hand trailed down to toy with the folds of their pussy, the conflicting sensations making Sans bite down on his hand to muffle the groan. Papyrus turned his head to the side, clenching a fist in front of his mouth and letting out a soft breath. Sans often marvelled at his brother’s ability to keep quiet during things like this while he tended to lose control over his vocals.  
“We were in the ring,” Papyrus repeated, “and we were in the middle of a performance. And then...” he moaned as Sans’ fingers breached their entrance.  
“Go on,” he said, voice rough with want.  
Papyrus’ hand tightened around their dick. “And then you...you lifted up the dress and showed everyone our underclothes.”  
Sans shivered at the throb that resonated through their magic as he said that. He knew that Papyrus had a bit of a thing for showing off, but it was always a pleasant surprise to feel just how excited he got when indulging in it.  
“And you made me help form our magic right there in front of everybody. And you told me to touch ourself and show everyone how much I like people to s-s-eeEE!”  
The last word was pitched into a squeak as Sans slid another finger in and scissored them. He used his other hand to grab at Papyrus’ ribs, squeezing in all the right places.  
“You do like it, don’t you,” he panted, cheeks flushing as he felt the pleasure building. “You love being lewd in the tent hoping anyone might walk in and see us pleasuring ourselves. I know how excited you get thinking about the whole audience watching us while we put on a show. You can’t hide it from me, Paps. I can always tell when you’re thinking about it. You don’t even try to hide it, do you?”  
Papyrus whined, composure slipping. His movements became jerky and erratic, squeezing hard enough to be nearly painful. Sans moaned, thumbing their clit while he talked. “So dirty. So lewd, Papyrus. Your sweet little innocent act won’t fool anyone if they see you fucking yourself on your bro’s hand--!”  
Papyrus cried out, spine arching as magic exploded out of both constructs. Sans bit down on his hand hard, orgasmic shout muffled against his bones.  
The high lasted for several moments, and then they slumped to the bed. The already soiled sheets were suddenly very uncomfortable against their bare bones, and Sans was suddenly very glad for the lack of nightclothes per Metta’s “beauty sleep rules”.  
“We gotta clean all of this up now,” Papyrus mumbled, sleep already seeping into his voice. Sans grunted, not looking forward to getting up and actually cleaning the mess. He balled up the soiled sheets and undersheet and threw them to the corner of the room.  
“There. Problem solved.”  
Papyrus frowned, but rested his head on Sans’ shoulder nonetheless. “We’re just going to have to clean that up tomorrow.”  
“Which means that we get to sleep tonight.” Sans pressed a kiss to Papyrus’ forehead and closed his eyes. “Try and dream about something different this time, ‘kay? I want to actually sleep a little.”  
Papyrus blushed and shoved him halfheartedly. “Shut up.”  
“Gladly."


End file.
